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Herein we report the first example of a strategy for peptide functionalization through the generation of selenocysteine electrophile in 5‐ and 6‐endo‐dig cyclization reactions. This simple approach allows bio‐conjugation of selenocystine‐based peptides. The developed protocol is based on copper(II) bromide mediated reactions of selenocystine with either 2‐propargyl N‐heterocycles through 5‐endo‐dig closure or with 2‐ethynylbiaryls through 6‐endo‐dig closure. It allows construction of indolizinium moiety on selenocysteine residue as well as formation of polyaromatic fragment bonded to selenium in a simple one‐pot process under mild reaction conditions.

The magneto-mechanical approach is a powerful technique used in many different applications in biomedicine, including remote control enzyme activity, cell receptors, cancer-selective treatments, mechanically-activated drug releases, etc. This approach is based on the use of a combination of magnetic nanoparticles and external magnetic fields that have led to the movement of such nanoparticles with torques and forces (enough to change the conformation of biomolecules or even break weak chemical bonds). However, despite many theoretical and experimental works on this topic, it is difficult to predict the magneto-mechanical effects in each particular case, while the important results are scattered and often cannot be translated to other experiments. The main reason is that the magneto-mechanical effect is extremely sensitive to changes in any parameter of magnetic nanoparticles and the environment and changes in the parameters of the applied magnetic field. Thus, in this review, we (1) summarize and propose a simplified theoretical explanation of the main factors affecting the efficiency of the magneto-mechanical approach; (2) discuss the nature of the MNP-mediated mechanical forces and their order of magnitude; (3) show some of the main applications of the magneto-mechanical approach in the control over the properties of biological systems.

In this article, we study the competing oxygen evolution and hydrogen peroxide (H 2 O 2 ) formation reactions for periodic models of graphene with different active-site concentrations by means of density functional theory (DFT) calculations. Linking the DFT calculations to ab-initio thermodynamic considerations in conjunction with microkinetic modeling enables gaining deep insights into the activity and selectivity trends of graphene-based electrodes as a function of applied bias. We illustrate that both the coverage of intermediates on the electrode surface and the applied electrode potential have a significant effect on the Faradaic efficiency for the electrocatalytic production of H 2 O 2 . The presented approach to study overpotential-dependent selectivity trends allows deriving design criteria for peroxide formation, which may serve as a guideline for further studies to realize selective formation of H 2 O 2 using carbon-based materials.